Up to 77% of young Americans with severe mental illnesses (SMI: schizophrenia and severe mood disorders) smoke, a rate that is up to five times higher than the rate of daily smoking in other young adults. This group goes on to experience very high rates of morbidity and mortality due to smoking-related diseases. Motivational interventions can engage SMI smokers into cessation but have not been tested in young, transitional age adults with SMI, who require interventions that address their unique characteristics and needs. The investigators have developed a basic, easy-to-use, motivational electronic decision support system (EDSS) tailored for smokers with SMI. Although pilot testing in middle-aged SMI adults provided promising results, recent pilot work among young SMI smokers indicated that the EDSS, although motivating, required further development. To address the need for low cost, effective motivational interventions for this group, we propose here to further develop and then test our theory-based EDSS -- the product will be an easy-to-use and implement web-based intervention to motivate young SMI smokers to quit with effective cessation treatments. The EDSS development proposed here will be based on the Theory of Planned Behavior, which states that population-specific beliefs, attitudes, social norms, and perceived behavioral control regarding a health behavior can be changed to increase intention and behavior enactment. In Year 1, we will identify the beliefs of young SMI smokers that impede use of cessation treatments. The EDSS will then be revised to change these beliefs (and related attitudes, social norms and perceived behavioral control) with new design, text, interactive exercises, and video patient stories. The revised EDSS will be field-tested for usability among young SMI smokers and improved as needed. In Year 2, we will conduct an RCT among 60 young smokers with SMI psychotic disorders comparing the EDSS to a computerized version of a standard smoking cessation pamphlet. Analyses will assess whether use of the EDSS results in greater clinician-confirmed initiation of cessation treatment, as well as changes in beliefs about treatment. This study will set the stage for an R01 application to conduct a full RCT to test the efficacy of the revised EDSS to motivate young SMI smokers to use cessation treatment. The ultimate goals of this intervention are to extend life expectancy, reduce illness burdens and increase quality of life for Americans with SMI.